Synthesis and electrospray mass spectrometric studies on a chiral, non-racemic, phosphoramide receptor molecule
摘要:
The synthesis of a class of macrocyclic receptors containing a phosphoramide is described. The preliminary evaluation of this new receptor for interactions with several homochiral amines using electrospray ionisation mass spectrometry is also described. (C) 1999 Elsevier Science Ltd. All rights reserved.
Enzymatic synthesis of enantiopure aromatic secondary alcohols (including substituted, hetero-aromatic and bicyclic structures) was carried out using halophilic alcohol dehydrogenase ADH2 from Haloferax volcanii (HvADH2). This enzyme showed an unprecedented substrate scope and absolute enatioselectivity. The cofactor NADPH was used catalytically and regenerated in situ by the biocatalyst, in the presence
This report describes the enantioselective reduction of structurally diverse α,β-unsaturated ketones and aryl ketones by perakine reductase (PR) from Rauvolfia. This enzymatic reduction produces α-chiral allylic and aryl alcohols with excellent enantioselectivity and most of the products in satisfactory yields. Furthermore, the work demonstrates 1 mmol scale reactions for product delivery without any
2-Azanorbornyl Alcohols: Very Efficient Ligands for Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation of Aromatic Ketones
作者:Diego A. Alonso、Sofia J. M. Nordin、Peter Roth、Tibor Tarnai、Pher G. Andersson、Marc Thommen、Ulrich Pittelkow
DOI:10.1021/jo991914a
日期:2000.5.1
2-Azanorbornyl-derived amino alcohols were prepared and evaluated as ligands in the Ru(II)-catalyzed asymmetric transfer hydrogenation of aromatic ketones. To improve selectivity and rate, the structure of the ligand was optimized. Acetophenone was reduced using 0.5 mol % catalyst in 40 min in 94% ee. This system was also able to reduce a wide range of aromatic ketones to the corresponding alcohols, while maintaining
Preparative asymmetric reduction of ketones in a biphasic medium with an (S)-alcohol dehydrogenase under in situ-cofactor-recycling with a formate dehydrogenase
The substrate range of a novel recombinant (S)-alcohol dehydrogenase from Rhodococcus erythropolis is described. In addition, an enzyme-compatible biphasic reaction medium for the asymmetric biocatalytic reduction of ketones with in situ-cofactor regeneration has been developed. Thus, reductions of poorly water soluble ketones in the presence of the alcohol dehydrogenase from R. erythropolis and a
A Simple Protocol for the One Pot Synthesis of Chiral Secondary Benzylic Alcohols by Catalytic Enantioselective Reduction of Aromatic Ketones
作者:Viviana L. Ponzo、Teodoro S. Kaufman
DOI:10.1055/s-2002-32598
日期:——
A simple and efficient protocol for the one-pot catalytic enantioselective reduction of prochiral aromaticketones mediated by in situ prepared catalysts derived from ( S)-(-)-diphenyl-pyrroli- din-2-yl-methanol, is reported.